<template>
	<div class="upload-file">
		<el-upload
				ref="fileUpload"
				:action="uploadFileUrl"
				:before-upload="handleBeforeUpload"
				:file-list="fileList"
				:headers="headers"
				:limit="limit"
				:on-error="handleUploadError"
				:on-exceed="handleExceed"
				:on-success="handleUploadSuccess"
				:show-file-list="false"
				class="upload-file-uploader"
				multiple
		>
			<!-- 上传按钮 -->
			<el-button type="primary">选取文件</el-button>
		</el-upload>
		<!-- 上传提示 -->
		<div v-if="showTip" class="el-upload__tip">
			请上传
			<template v-if="fileSize"> 大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b></template>
			<template v-if="fileType"> 格式为 <b style="color: #f56c6c">{{ fileType.join('/') }}</b></template>
			的文件
		</div>
		<!-- 文件列表 -->
		<transition-group class="upload-file-list el-upload-list el-upload-list--text" name="el-fade-in-linear" tag="ul">
			<li v-for="(file, index) in fileList" :key="file.uid" class="el-upload-list__item ele-upload-list__item-content">
				<el-link :href="`${baseUrl}${file.url}`" :underline="false" target="_blank">
					<span class="el-icon-document"> {{ getFileName(file.name) }} </span>
				</el-link>
				<div class="ele-upload-list__item-content-action">
					<el-link :underline="false" type="danger" @click="handleDelete(index)">删除</el-link>
				</div>
			</li>
		</transition-group>
	</div>
</template>

<script setup>
import {getToken} from '@/utils/auth'

const props = defineProps({
	modelValue: [String, Object, Array],
	// 数量限制
	limit: {
		type: Number,
		default: 5,
	},
	// 大小限制(MB)
	fileSize: {
		type: Number,
		default: 5,
	},
	// 文件类型, 例如['png', 'jpg', 'jpeg']
	fileType: {
		type: Array,
		default: () => ['doc', 'xls', 'ppt', 'txt', 'pdf'],
	},
	// 是否显示提示
	isShowTip: {
		type: Boolean,
		default: true
	}
})

const {proxy} = getCurrentInstance()
const emit = defineEmits()
const number = ref(0)
const uploadList = ref([])
const baseUrl = import.meta.env.VITE_APP_BASE_API
const uploadFileUrl = ref(import.meta.env.VITE_APP_BASE_API + '/common/upload') // 上传文件服务器地址
const headers = ref({Authorization: 'Bearer ' + getToken()})
const fileList = ref([])
const showTip = computed(
		() => props.isShowTip && (props.fileType || props.fileSize)
)

watch(() => props.modelValue, val => {
	if (val) {
		let temp = 1
		// 首先将值转为数组
		const list = Array.isArray(val) ? val : props.modelValue.split(',')
		// 然后将数组转为对象数组
		fileList.value = list.map(item => {
			if (typeof item === 'string') {
				item = {name: item, url: item}
			}
			item.uid = item.uid || new Date().getTime() + temp++
			return item
		})
	} else {
		fileList.value = []
		return []
	}
}, {deep: true, immediate: true})

// 上传前校检格式和大小
function handleBeforeUpload(file) {
	// 校检文件类型
	if (props.fileType.length) {
		const fileName = file.name.split('.')
		const fileExt = fileName[fileName.length - 1]
		const isTypeOk = props.fileType.indexOf(fileExt) >= 0
		if (!isTypeOk) {
			proxy.$modal.msgError(`文件格式不正确，请上传${props.fileType.join('/')}格式文件!`)
			return false
		}
	}
	// 校检文件名是否包含特殊字符
	if (file.name.includes(',')) {
		proxy.$modal.msgError('文件名不正确，不能包含英文逗号!')
		return false
	}
	// 校检文件大小
	if (props.fileSize) {
		const isLt = file.size / 1024 / 1024 < props.fileSize
		if (!isLt) {
			proxy.$modal.msgError(`上传文件大小不能超过 ${props.fileSize} MB!`)
			return false
		}
	}
	proxy.$modal.loading('正在上传文件，请稍候...')
	number.value++
	return true
}

// 文件个数超出
function handleExceed() {
	proxy.$modal.msgError(`上传文件数量不能超过 ${props.limit} 个!`)
}

// 上传失败
function handleUploadError(err) {
	proxy.$modal.msgError('上传文件失败')
}

// 上传成功回调
function handleUploadSuccess(res, file) {
	if (res.code === 200) {
		uploadList.value.push({name: res.fileName, url: res.fileName})
		uploadedSuccessfully()
	} else {
		number.value--
		proxy.$modal.closeLoading()
		proxy.$modal.msgError(res.msg)
		proxy.$refs.fileUpload.handleRemove(file)
		uploadedSuccessfully()
	}
}

// 删除文件
function handleDelete(index) {
	fileList.value.splice(index, 1)
	emit('update:modelValue', listToString(fileList.value))
}

// 上传结束处理
function uploadedSuccessfully() {
	if (number.value > 0 && uploadList.value.length === number.value) {
		fileList.value = fileList.value.filter(f => f.url !== undefined).concat(uploadList.value)
		uploadList.value = []
		number.value = 0
		emit('update:modelValue', listToString(fileList.value))
		proxy.$modal.closeLoading()
	}
}

// 获取文件名称
function getFileName(name) {
	// 如果是url那么取最后的名字 如果不是直接返回
	if (name.lastIndexOf('/') > -1) {
		return name.slice(name.lastIndexOf('/') + 1)
	} else {
		return name
	}
}

// 对象转成指定字符串分隔
function listToString(list, separator) {
	let strs = ''
	separator = separator || ','
	for (let i in list) {
		if (list[i].url) {
			strs += list[i].url + separator
		}
	}
	return strs != '' ? strs.substr(0, strs.length - 1) : ''
}
</script>

<style lang="scss" scoped>
.upload-file-uploader {
	margin-bottom: 5px;
}

.upload-file-list .el-upload-list__item {
	border: 1px solid #e4e7ed;
	line-height: 2;
	margin-bottom: 10px;
	position: relative;
}

.upload-file-list .ele-upload-list__item-content {
	display: flex;
	justify-content: space-between;
	align-items: center;
	color: inherit;
}

.ele-upload-list__item-content-action .el-link {
	margin-right: 10px;
}
</style>
